Some tests create a table and try to use it before regions get assigned

I inadvertently did some unit test stress testing this weekend by running mvn test -P runAllTests on a machine that also had other processes going on. The overall sluggishness led to a number of failed tests that were caused by a table being created using HBaseAdmin#createTable, which only blocks for meta to get updated and not for the region to actually get assigned a RegionServer. Quick fix is to use HBaseTestingUtility#createTable whenever possible.